Letter from Wilder Penfield to Nolan D.C. Lewis, July 5, 1935.
Letter from Wilder Penfield to Nolan D.C. Lewis, June 13, 1935.
Letter from Wilder Penfield to Otfrid Foerster, November 9, 1934.
Letter from Wilder Penfield to Paul and Mae Myers, July 16, 1931.
Letter from Wilder Penfield to Paul F. Myers, March 5, 1928.
Letter from Wilder Penfield to Paul Mayers, May 19, 1930.
Letter from Wilder Penfield to Paul Mayers, October 11, 1928.
Letter from Wilder Penfield to Paul Mayers, October 17, 1929.
Letter from Wilder Penfield to Paul Myers, August 18, 1930.
Letter from Wilder Penfield to Paul Myers, January 19, 1929.
Letter from Wilder Penfield to Paul Myers, January 26, 1931.
Letter from Wilder Penfield to Paul Myers, October 22, 1930.
Letter from Wilder Penfield to Paul Myers, September 28, 1929.
Letter from Wilder Penfield to Paul Myers, September 4, 1930.
Letter from Wilder Penfield to Professor J.C. Simpson, December 30, 1929.